ارزيابي تاثير متقابل منبع تغذيه اي و تنوع گياهان زراعي بر كارآيي مصرف نهاده ها در الگوهاي مختلف كشت

Interaction of nutrient resource and crop diversity on resource use efficiency in different cropping systems

به منظور بررسي اثر تنوع گياهي و نوع منبع تغذيه اي بر كارآيي مصرف آب و عناصر غذايي، آزمايشي به صورت كرت هاي خردشده بر پايه طرح بلوك هاي كامل تصادفي با سه تكرار در دو سال زراعي 1385-1384 و 1386-1385 در مزرعه تحقيقاتي دانشكده كشاورزي دانشگاه فردوسي مشهد به اجرا درآمد. تيمارهاي مورد بررسي دو منبع كود دامي و كود شيميايي در كرت هاي اصلي و كشت مخلوط سه واريته سويا (Glycine max L.) (ويليامز، سحر و گرگان 3)، كشت مخلوط سه گونه ارزن (ارزن معمولي (Panicum miliaseum L.)، مرواريدي (Pennisetum glaucum L.) و دم روباهي (Setaria italic L.)، كشت مخلوط ارزن معمولي- سويا- كنجد (Sesamum indicum L.) و كشت مخلوط ارزن- كنجد- شنبليله(Trigonella foenum-graecum L.)-زنيان(Trachyspermum ammi L.) همراه با تك كشتي هر يك از گياهان مورد بررسي در كرت هاي فرعي را شامل مي شد. نتايج نشان داد كه الگوهاي مختلف كشت از نظر كارآيي مصرف آب اختلاف معني داري داشتند. در سال زراعي اول، در بين كشت هاي مخلوط مورد بررسي، مخلوط سه گونه ارزن و مخلوط ارزن، سويا و كنجد، داراي بيشترين كارآيي مصرف آب برحسب عملكرد بيولوژيكي بودند. در سال زراعي دوم در بين الگوهاي مخلوط مورد بررسي، كشت مخلوط سه گونه ارزن بيشترين كارآيي مصرف آب را برحسب عملكرد بيولوژيكي داشت. برترين الگوي مخلوط از نظر ميزان نيتروژن، فسفر و پتاسيم موجود در بافت گياهي در واحد سطح، مخلوط سه واريته سويا و مخلوط ارزن، سويا و كنجد بود. در سال زراعي اول، در بين كشت هاي مخلوط مورد بررسي، كشت مخلوط سه واريته سويا بيشترين كارآيي مصرف عناصر غذايي را داشت. در سال زراعي دوم، در بين الگوهاي مخلوط، كشت مخلوط سه واريته سويا، مخلوط ارزن، سويا و كنجد و مخلوط ارزن، كنجد، شنبليله و زنيان از نظر كارآيي مصرف عناصر غذايي، اختلاف معني داري با هم نداشته و برتر از مخلوط سه گونه ارزن بودند. در هر دو سال زراعي، كشت هاي مخلوط ارزن، سويا و كنجد و مخلوط ارزن، كنجد، شنبليله و زنيان داراي كارآيي جذب نيتروژن و فسفر بالايي بوده و اختلاف معني داري با هم نداشتند. از نظر كارآيي جذب پتاسيم نيز مخلوط سه گونه ارزن، سويا و كنجد بهتر از ديگر كشت هاي مخلوط عمل كرد. در اين مطالعه نوع منبع تغذيه اي بر كارآيي مصرف آب و عناصر غذايي تاثير معني داري نداشت.

Introduction Conventional operations in fields, soil and water management are not efficient and loss of and damage to the environment are considerable (Lal, 2000). Crop diversity and understanding the complex interactions between environmental and socioeconomic factors are approaches to make better use of limited resources (Tengberg et al., 1998). The most diverse ecosystems have a higher production under environment stress conditions compared with ecosystems with low diversity due to the better efficiency in the use of water, radiation and nutrients (Hulugalle & al, 1986; Walker & Ogindo, 2003). Materials and Methods In order to investigate the effects of crop diversity and nutrient source on resource use efficiency, a split plot experiment was conducted based on complete randomized blocks with 3 replications at the Agricultural Research Station, the Ferdowsi University of Mashhad, Iran, during 2006 and 2007. The treatments included manure and chemical fertilizers as the main plots and intercropping of 3 soybean varieties (Williams, Sahar and Gorgan3), intercropping of 3 Millet species (common millet, foxtail millet and pearl millet), intercropping of millet, soybean and sesame (Sesamum indicum) and intercropping of millet, sesame, fenugreek (Trigonella foenum-graecum) and ajowan (Trachyspermum ammi) as sub plots. Results and Discussion The results indicated that in the first year, intercropping of 3 Millet species and intercropping of millet, soybean and sesame showed the highest water use efficiency (WUE) based on biological yield. In the second year, intercropping of 3 millet species showed the highest WUE based on biological yield. The highest concentrations of nitrogen, phosphorous and potassium in crop tissues were observed in intercropping of 3 soybean varieties and intercropping of millet, soybean and sesame. In the first year, intercropping of 3 soybean varieties showed the highest nutrient use efficiency (NUE). In the second year, intercropping of 3 soybean varieties, intercropping of millet, soybean and sesame and intercropping of millet, sesame, fenugreek and ajowan showed the highest NUE. In the two years, intercropping of millet, soybean and sesame and intercropping of millet, sesame, fenugreek and ajowan showed the highest nitrogen and phosphorus absorption efficiency (NAE). Intercropping of millet, soybean and sesame showed the highest potassium uptake efficiency. In this study, nutrient resource did not have a significant effect on water and nutrient use efficiency. The research results have indicated that often nitrogen amount and use efficiency in legume and non legume intercropping were higher than monocultures. This indicates the synergist effect in the intercroppings (Vandermeer, 1989; Szumigalski & Van Acker, 2006). In general, the different benefits of diversity and better use of available inputs are obtained by increasing the diversity of crops and proper selection of plants cultivated in intercropping systems and crop rotations in monoculture systems Acknowledgments This research (044 p) was funded by the Vice Chancellor for Research of the Ferdowsi University of Mashhad, which is hereby acknowledged. References Hulugalle, N.R., and Lal, R. 1986. Soil water balance of intercropped maize and cowpea grown in tropical hydromophic soil Western Nigeria. Agronomy Journal 74: 86-90. Lal, R. 2000. Soil management in the developing countries. Soil Science 105: 57-72. Szumigalski, A.R., and Van Acker, R.C. 2006. Nitrogen yield and land use efficiency in annual sole crops and intercrops. Agronomy Journal 98: 1030-1040. Tengberg, A., Ellis-Jones, J., Kiome, R., and Stocking, M. 1998. Applying the concept of agrodiversity to indigenous soil and water conservation practices in eastern Kenya. Agriculture, Ecosystems and Environment 70: 259-272. Vandermeer, J. 1989. The ecology of intercropping. Cambridge University Press, Cambridge 237 pp. Walker, S., and Ogindo, H.O. 2003. The water budget of rainfed maize and bean intercrop. Physics and Chemistry of the Earth 28: 919-926.